Cancer cells in the human body have several proteins called antigens on their surface. The body’s immune system, specifically T-lymphocytes, recognize the tumor antigens and can be used as potential targets in cancer therapy.1 This type of treatment is called immunotherapy. What are dendritic cells? How can they be used as cancer vaccines?
What is immunology?
Immunology is a study of the body’s immune system. The immune system protects the body against infection and disease.6 It is activated when the body encounters a pathogen (bacteria, virus, or other diseases). The immune system retains a memory of the pathogen so that it can mount a rapid and effective response in case of re-infection.6
How is immunology used to treat cancer?
Immunotherapy is a biological treatment that boosts the body’s natural ability to fight cancer.7 It works by improving the functioning of the immune system through substances made in the body or the laboratory. Immunotherapy can stop or slow the growth of cancer cells, stop cancer from spreading, and help the immune system destroy cancer cells.7
Cancer vaccines are a type of immunotherapy. The vaccine exposes the body’s immune system to antigens found on tumor cells. This makes it possible for the immune system to identify and destroy the cancer cells.
What is a dendritic cancer cell vaccine?
Leukocytes are blood cells that are a part of the immune system. They fight infection and disease in the body. Dendritic cells are a rare type of leukocyte that are antigen-presenting cells. In other words, their function is to process the antigens present on the surface of cells and present them to T-lymphocytes (white blood cells that protect the body from infection and help fight cancer).2 The ability of dendritic cells to recognize antigens on the surface of cancer cells and present them to the body’s immune system makes them a very powerful weapon in cancer treatment.
Dendritic cell cancer vaccines are developed by isolating dendritic cells from the patient’s blood. The dendritic cells are loaded with tumor antigens in the laboratory. They are then administered in the form of a therapeutic cancer vaccine. The vaccine essentially “educates” the patient’s immune system to generate an effective T-cell response against the tumor.4 Dendritic cells, therefore, play a critical role in inducing anti-tumor immunity.1
What kinds of cancers can be treated with dendritic cancer vaccines?
Clinical trials have been conducted on dendritic cell vaccination in patients with melanoma and non-Hodgkin’s lymphoma. The vaccine was found to induce an anti-tumor immune response and regression in the tumor.1 Sipuleucel-T (Provenge) is a DC-based vaccine that has been approved by the FDA for the treatment of advanced prostate cancer.3 Outside the United States, a dendritic cell cancer vaccine called APCEDEN has been approved for four types of cancers – ovarian cancer, prostate cancer, non-small cell lung carcinoma, and colorectal cancer.3 The University of Pennsylvania has conducted a study on dendritic cell vaccination for advanced melanoma.5
Dendritic cell cancer vaccines are well-tolerated and have a good safety profile. They have been shown to improve survival in cancer patients. Personalized DC-based vaccines have been tested in ovarian cancer patients with a demonstrable anti-tumor response and longer progression-free survival.3